Centrifugal pulp-screen.



No. 309,041. PATENTED JAN. 2, 1906. J. H. BAKER, G. F. SHEVLIN & F. H.BAKER.

UENTRIFUGAL PULP SCREEN,

APPLICATION FILED .AUG.30,1905.

2 SHEETS-SHEET 1.

No. 809,041. PATENTBD JAN. 2, 1906. J. H. BAKER, G. F. SHEVLIN &: F. H.BAKER.

OENTRIFUGAL PULP SCREEN.

APPLICATION FILED AUG. 30, 1905.

2 SHEETS-SHEET 2.

.1101; .lloll UNITED STATES PATENT OFFICE.

JAMES H. BAKER, GEORGE F. SHEVLIN, AND FREDERICK H. BAKER, OF

SARATOGA SPRINGS, NEW YORK, ASSIGNORS TO BAKER AND SHEV- LIN COMPANY, OFSARATOGA SPRINGS, NEW YORK, A CORPORATION OF NEW YORK.

CENTRIFUGAL PULP-SCREEN.

devices we have found that stock would gather behind the blades of thebeater-wheels and tend to throw the wheels out of balance. We have alsofound that the exitslots for the stock from the central receivingwell tothe delivery portions of the beaterwheels would not answer for allgrades of stock. It is sometimes necessary to obtain access to theinterior of the machine for examination of the screen-plates, &c., andheretofore it has been necessary to partly dismantle the machine,certainly to remove one or more of the panels of the outer casing, Wehave also found it necessary to provide for the discharge of anincreased volume of air from between the screen-plates and easing on theside of delivery of the good stock otherwise the pent-up pressure willseriously interfere with the full working of the screenplates. We havealso found it necessary to provide improved means for delivering thestock to the centrifugal machine, mixing it with a regulatable quantityof water, and preventing the suction of air therewith to any appreciableextent because of the action of the beater-wheels.

In the machine of our present improvement we provide fillets which weplace behind the blades of the beater-wheels and within the centralreceiving-well, so as to prevent the stock gathering behind the bladesof the beater-wheels, and in this way we overcome any tendency to throwthe wheels out of balance, and we provide adjacent to the exit of thecentral receiving-well adjustable blades which may be moved to increaseor diminish the atmospheric pressure at the slot, so that the opening issuitable for the grade of stock passing through the centrifugal machine.In order that access may be obtained Specification of Letters Patent.

Application filed August 30, 1905. Serial No. 276,345.

Patented Jan. 2, 1906.

within the casing of the machine for the purpose of examining thescreens, &c., we provide openings in the external casing with shuttersor slide-plates that may be simply raised to obtain access within thecasing. This obviates the necessity of dismantling the machine in anyrespect.

In Letters Patent granted to us, No. 686,962, November 19, 1901, weillustrated and described a device for relieving the pentup air-pressurebetween the casing and the screen-plates; but we have found byexperience that this operates only to a certain extent, but notsufficient for the full operation of the machine, and we have thereforepro vided adjacent to the top trough for the good stock an opening forthe discharge of air from the lower part of the annular chamber.

In our improved machine we provide devices for more perfectly andeffectually delivering the stock to the centrifugal'pulpscreen, mixingit with a regulatable quantity of water, and passing the same from areceiving-vat into the machine, so as to avoid as far as possible theentrance of air into the machine to an appreciable extent.

The means for oiling and cooling the vertical shaft of our improvedcentrifugal pulpscreen were specifically shown and described in LettersPatent No. 738,513, of September 8, 1903. In the device of this patent aflange was shown extending around the oilreceptacle'to prevent foreignsubstances getting in and mixing with the oil to its detriment; but wehave found by experiment that this shaft throws oiland it is likely toget out and be lost as well as to cause a spat-- tering that has to becleaned up. In our present improved machine we have provided a flangethat extends down within the oil vessel, so as to receive any oil thrownoff from the oil-shaft and cause the same to return to the oil vessel.

All of these parts will hereinafter be more particularly described andclaimed.

In the drawings, Figure 1 is a vertical section and partial elevationrepresenting our complete improved pulp-screen. Fig. 2 is a verticalsection and partial elevation, in larger size, of the oiling and coolingdevices employed by us at the lower end of the revoluble shaft. Fig. 3is a sectional plan about trifugal screen-plates, a pipe d beingconnectshaft Z) and receive the good stock and slivers.

tric to the other.

parts, so as to provide a firm structure, and

on the dotted line at a; of Fig. 1 and in larger I size. Fig. 4 is anelevation of a portion of the said receivingwell, showing the exit-slotsand the means for adjusting the proportions of the same. Fi 5 is avertical section about on the dotted fine y 'y, Fig. 3, and on a scaleagreeing with Fig. 3; and Fig. 6 is an elevation, partially in section,of the water-discharge nozzle.

A platform or supporting structure a may be employed for thbed-support aof the machine, or the bed-support a may rest upon any suitablefoundation. The vertical revoluble shaft 7) passes up centrally throughthe machine, with its lower end in the oiling and cooling step-bearingdevices 1), preferably the same as that described and illustrated in ourLetters Patent No. 738,513, and b is a pulley at the upper end of thevertical shaft 1). A number of standards 61?, secured to and risingfromthe bed-support (1., carry the major parts of the machine, among thefirst of which are the annular concentric cast-metal troughs c, d, whichsurround the vertical The outer metal trough c at one side is providedwith a horizontal air-exit opening 0, and adjacent to this opening thebottom of the trough is removed and a lower dischargetrough c secured tothe flanged edges of the trough c, and a tank 0 is secured to the sidesof the troughs c and c, the air-opening 0 providing for the entrance ofair to the annular chamber between the casing and the segmentalscreen-plates, while the good stock from the said annular chamberdelivered into the trough c discharges into the trough cand from thereinto the tank 0 On the other side of the machine a portion of the bottomof the annular concentric cast-metal trough cl is removed and a troughd, fitting below the opening, serves as a discharge for the sliverswhich gather in the trough d within the cened to the trough d to carrythe slivers away either as a waste product or to be again treated inother machines, if desired. We also connect the discharge water-pipe 26from the water-chamber of the step to the sliver-trough of the screen towash out the slivers as fast as they drop into the trough.

The upper outer edges of the annular concentric cast-metal troughs c dare flanged, and we provide ring-flanges e e, secured to these flangesand coming outside of and in turn secured to the segmental casing f,formed of panels, and the circular segmental screen-plates g, the one ofwhich is concen- We .provide a cover-plate h, open in the center and inturn provided with ring-frames 2 3, secured thereto and coming outsideof the upper ends of the segmental casingf and screen-plates g and inturn secured to said in the cover h are openings and perforated plates hto the annular chamber between the casingf and plates g for the reliefof the pent-up air in said annular chamber and for washing thescreen-plates, as described in Letters Patent heretofore granted to us,Nos. 693,215 and 735,444.

As shown in Fig. 3, we usually employ four panels or plates to thecasing], between which are located hollow air-vent columns 9, as shownand described in our prior patent, No. 727,878, and to the sides ofwhichthe plates or panels forming the segmental casing f are secured. Toobtain accessto the interior of this casing for any purpose whatsoever,we provide openings, preferably one in each panel, and around eachopening place a frame f, the frames being so constructed with sideslideways as to receive the verti- Cally-removable shutter f at thelower end of which is a loop-handle. As the said shutter slides and fitsin recessed edges, none of the materials can escape from the annularchamber, said parts being liquid and pulp ti it.

g represents the circular segmental screenplates of the usual form andconstruction heretofore employed by us and described in our patents,said screen-plates rising from the flange which divides the troughs c d.

A cylinder 11, having an inletpipe 4, is secured to the cover 71., thesame preferably having a flange passing down into the central opening ofthe cover and constructed with a cleaning-out opening 5 and hollowcover-inclosure i, having a deflector 4 as shown and described in ourformer patent,-. No. 727,878.

The water-pipe 6 is provided with a valve 7 and terminates in adischarge-nozzle 8. This discharge-nozzle 8 is narrow in one di-.rection and of a maximum width in the other direction. (See Fig. 6.)

9 represents a pipe for conveying along the paper-stock, in which is avalve 10.

Both the pipes 6 and 9 turn with bends from a horizontal to a verticaldirection and enter the vat 11. This vat is provided with an opening 12and sliding gate 14, and a pipe 13 connects the vat at the opening 12with the pipe 4. It will be noticed that the lower end of the pipe 9 isWell down in the vat 11, and as the stock is delivered said end isprobably immersed. Furthermore, this lower end of the pipe comes belowthe limits of the opening 12, while the discharge-nozzle 8 for the wateris above this opening, so that the stock does not come into contact withthe nozzle 8. In this vat the stock is received and as it enters isdiluted by the water from the pipe 6 and nozzle 8, and the valves 7 and10 provide for regulating the quantities of stock and water, so as toobtain the desired consistency of the material before it enters thepulp-screen; The height of the gate 14 may be regulated as desired; butit is preferable make the same below the level of the pulp in the vat,so as to prevent the suction of the machine drawing air into the same asfar as possible.

The beater-wheels employed byus are similar to those in our copendingapplication of November 5, 1904, Serial No. 231,503, and they comprisethe hub k, having inclined flanges k 70 formed therewith. With theseparts are also formed radial curved partitionwalls and flanges 16, 17,and 18, the flanges 16 and 17 being curved and theflanges 18 beingvertical and radial. The diameter of the inclined flange k is slightlygreater than the diameter of the inclined flange 7c.

We provide a top plate Z and flanges 19, and betwween the same and theinclined flanges are located the cylinder m and flanges m. The curvedradial blades n are both within and without the cylinder m, and in thestructure of the beater-wheels these blades are riveted to the flanges16, 17, 18, and 19, as well as to the flanges m of the cylinder, so asto form a substantially integral structure, there being in the cylinderm adjacent to the convex-surfaces of the blades, slots 20. In connectionwith these slots 20, and as especially shown in Figs. 3 and 4, weprovide adjacent blades 0. These overlie the outer surface of thecylinder m and are provided with slots through which pass screws intothe cylinder, and by these blades 0 the size of the slots 20 can bereadily regulated in proportion to the kinds of stock to be treated orits consistency. This adjustment can be effected by removing one panelof the outside casing and one section of screen-plates, this leaving thebeater-wheels exposed and by turning all the adjustable blades 0 can beadjusted.

' The hub' la is shorter than the depth of the blades n. Consequentlythe portions of the blades within the cylinder m are curved overdownward to meet the top of the hub, the cavity within the cylinder mand above the hub 16 being clear except for the shaft 1).

To prevent the stock gathering behind the blades of the beater-wheels,we provide fillets 1". These are shown in elevation in Fig. 1, in planand section in one direction in Fig. 3, and in vertical section in Fig.5. They are blades of peculiar form, the respective ends of which arebent at an inclination to the main portion, so that while the mainportion extends at an angle across between the inner portion of thecylinder m and the inner surface of the blades the ends bend in to fillthe angle and close up the cavity between said parts and thestraightparts of said fillets, so as to prevent the stock getting into theangles formed by the said cylinder and blades. These fillets are especially located at the upper part of the central well and reach downbehind the blades to just above the hub 76, at which place occurs thelower inclined part of the fillet, and thus leaving the cylinder belowthis point and the top of the hub of full size for the more perfectperformance of its functions, experiment having proved that the filletsare not required in the lower part of the well, where the most of thework is done in the centrifugal machine.

In Fig. 2 we have shown the oiling and cooling device for thesteppedlower end of the vertical revoluble shaft 6. This substantiallyagrees with the structure shown and described in our Patent No. 738,513,of September 8, 1903, and we provide in connection with this device thecover it, having an outer annular flange t and an inner annular flange tBetween these flanges the flange at the upper end of the oiling andcooling device, which forms a receptacle for the oil, is received. Theouter flange t prevents the entrance into the oil of foreign matter orpaper-stock, and the inner flange prevents the oil spattered by therevoluble shaft during its high speed from getting out of the oil vesseland returns it to the oil-receptacle, thus preventing a litter beingmade by the flying oil outside of the oil vessel, as well as preventingthe contamination of the oil by foreign mate rials mixing with the sameto its detriment.

We claim as our invention 1. In a centrifugal pulp-screen, thecombination with the beater-wheels, of devices secured behind the bladesof the beater-wheels and within the cylindrical portion and near theupper ends of the blades to prevent the stock gathering behind theblades.

2. In a centrifugal pulp-screen, the combination with the blades andcylindrical portions of the beater-wheels, of devices placed behind theblades and within the cylindrical part and near the upper part of theblades and extending across and filling the spaces behind the blades andmeans for attaching the same in place so as to ment of stock behind theblades.

3. In a centrifugal pulp-screen, the combination with the series ofcurved blades and the cylindrical portion bisecting the same and formingthe beaterwheels, of fillets comprising plates of metal with bent endsextending across behind the blades and in the angle formed by saidblades and cylinder with the end fitting in against the backs of theblades and surface of the cylinder, so as to prevent the stock gatheringbehind the blades.

4. Ina centrifugal pulp-screen, the combination with the blades andcylindrical portion forming the beater-wheels and in which cylindricalportion are exit-slots for the stock at the edges of and parallel withthe said blades, of means for lessening the size of said slots asdesired.

5. In a centrifugal pulp-screen, the combination with the blades andcylindrical portion forming'the beater-wheels and in which prevent thelodg gift cylindrical portion are exit-slots for the stock at the edgesof and parallel with said blades, of blades slotted transversely andscrews for attaching the same to the surface of the cylinder providingfor an adjustable relation of the blades to the cylinder for varying thesize of the slots.

6. In a centrifugal pulp-screen the combination with the circularsegmental screenplates and the annular concentric cast-metal troughs, ofthe segmental casing of panels surrounding the screen-plates andprovided with an opening of appreciable area, a frame surrounding saidopening and forming a slideway and a shutter-plate within said frame andagainst the surface of said casing to close off the opening in the panelof the casing for providing access thereto by raising the shutterplate.

7. In a centrifugal pulp-screen, the combi nation with the circularsegmental screenplates and the annular concentric cast-metal troughs, ofthe segmental casing of panels surrounding the screen-plates andprovided with an opening of appreciable area, of a device having aslidable relation with said panels and adapted to cover the openingtherein and a support therefor.

.8. In a centrifugal pulp-screen, the combination with the segmentalcasing and concentric circular segmental screen-plates within the same,of the annular concentric castmetal troughs, the one coming between theaforesaid parts at the base thereof and the other within thescreen-plates, a dischargetrough connected with the inner of saidconcentric troughs and located below the same on one side of themachine, a discharge-trough opening into the outer of said cast-metaltroughs and located beneath the same, and an exit-opening formed in thelatter trough parallel to the exit-opening of the latterdischarge-trough as an exit-opening for air from between the casing andthe screenplates.

9. In a centrifugal pulp-screen, the combination with the segmentalcasing of panels and the circular segmental screenplates connectedtherewith and within the same and the annular concentric cast-metaltroughs, the one between and the other within the said parts, of meanslocated at the upper portion of the casing and screen-plates, betweenthe panels of the segmental casing and also at one side of the outercast-metal trough as exists for the confined air between said casing andscreen-plates in the operation of the machine.

10. In a centrifugal pulp-screen, the combination with the segmentalcasin g f and circular screen-plates g, of the annular concentriccast-metal troughs e (Z, to which the aforesaid parts are connected, acurved. dischargetrough 0 below and opening into the trough c at oneside of the machine and having an exit-opening therefrom and of thelength of the said trough c and a parallel opening 0 at the side of thetrough c as an exit for the air from between the casing and thescreenplates.

1. 1. In a centrifugal pulp-screen, the combination with the segmentalcasingf and circular screen-plates g, of the annular concentriccast-metal troughs c d, to which the aforesaid parts are connected, acurved dischargetrough 0 below and opening into the trough c at onesideof the machine and having an exit-opening therefrom and of thelength of the said trough c and a parallel opening 0 at the side of thetrough c as an exit for the air from between the casing and thescreen-plates, and a tank 0 fitted up against the dischargetrough c andthe air-exit opening 0 of the trough c to receive the good stock in theoperation of the machine.

12. In a centrifugal pulp-screen, the combil nation with a verticalrevoluble shaft and a step-bearing for the lower end of the shaft andmeans for oiling and cooling the shaft at its bearing, of a cover to theoiling and cooling device provided with a downwardly-extending outerflange t and a second downwardly-extending inner flange i 13. In acentrifugal pulp-screen, the combination with a vertical revoluble shaftand a step-bearing for the lower end of the shaft and means for oilingand cooling the shaft at its bearing, of a device surrounding the shaftand extending over the oiling and cooling device and having 'partsassociated therewith and acting at the same time to prevent foreignparticles getting into the oiling and cooling device or oil spattered bythe revolving shaft from getting out.

14. In a centrifugal pulp-screen, the combination with a verticalrevoluble shaft and the beater-wheel, of an inlet-pipe for the stock tothe beaterwheel, a vat and pipe connecting the same to said inlet-pipe,a pipe for introducing the stock into the vat, a pipe for water and anozzle for admitting the water into the vat to mix with the stock andreduce its consistency, and a gate in the opening between said vat andpipe for regulating the extent of flow of the thinned stock to themachine.

15. In a centrifugal pulp-screen, the combination with a verticalrevoluble shaft and the beater-wheel, of an inlet-pipe for the stock tothe beater-wheel, a vat and pipe connecting the same to said inlet-pipe,a pipe for introducing the stock into the vat, a pipe for water and anozzle for admitting the water into the vat to mix with the stock andreduce its consistency and a gate in the opening between said vat andpipe for regulating the extent of the flow of the thinned stock to themachine, the said nozzle being narrow in one direction and of at leastthe diameter of the pipe in the opposite direction and located above thelower end of the gate and the discharge-opening formed thereby and thelower end of the inlet-pipe for the stock below the normal position ofthe lower end of the gate and inn nation with the segmental oasingf andcirou- I 5 lar screen-plates g of the annular cast-metal trough 0 comingbelow and between the Vertioal planes thereof, and an air-exit opening 0at one side of the trough c and in the same horizontal plane for thepent-up air from be- 20 tween the casing and screen-plates.

Signed by us this 2d day of August, 1905.

JAlWES H. BAKER. GEORGE F. SHEVLIN. FREDERICK H. BAKER. Witnesses:

CHARLES M. DAVISON, WM. OBRIER.

